Polyp prophylactic properties of polyacetylenes from carrots in patients with previous polypectomy-Px7 The study protocol of a multicentre binational randomised controlled trial.

introductionA large bowel cancer chemoprevention potential has been demonstrated by the consumption of carrots, which represent the major dietary source of polyacetylenes. Their interaction with cancer cells and enzyme systems of animals and humans has been systematically investigated over the last 15 years and has now been characterised as anti-inflammatory compounds with antineoplastic effect. Our objective is to investigate whether selected carrot species with a high content of the polyacetylenes falcarinol (FaOH) and falcarindiol (FaDOH) prevent neoplastic transformation and growth in humans, without side effects. METHODS AND ANALYSIS: We will conduct a multicentre prospective binational (Denmark and Sweden) randomised controlled trial, with the aim to test the clinical effects of adjuvant treatment with carrot juice in patients who had an excision of high-risk colon adenomas. Patients from six centres will be randomised to receive either anti-inflammatory juice made of carrots high in FaOH and FaDOH or placebo. We will compare the proportion of participants with recurrent adenoma and mean size of them, found in the 1-year follow-up colonoscopy between the two randomised groups. ETHICS AND DISSEMINATION: Informed written consent will be obtained from all participants before randomisation. The study was approved by the regional ethics committee in Denmark (ref. S-20230072) and Sweden (ref. 2024-04732-01). After completion of the trial, we plan to publish two articles in high-impact journals: one article on primary and secondary outcomes, respectively. TRIAL REGISTRATION NUMBER: NCT06335420.